Bodily fluids are collected for various reasons, including diagnosing illness, simple therapeutic removal, determining pregnancy, confirming or establishing levels of therapeutic agents, determining drug abuse, and profiling DNA composition. Blood, urine, and saliva are among the commonly collected bodily fluids for some or all of these purposes. Among these, saliva has an advantage over other fluids for ease of collection. This is especially true for drugs-of abuse-testing and for DNA testing.
Screening for drugs of abuse is performed by health professionals, law enforcement personnel, and government or private employers, among others. Substances of abuse that are commonly screened for include alcohol, cannabis, barbiturates, opioids, cocaine, amphetamines, and hallucinogens. For many such tests and testing environments, blood or urine collection is difficult, if not impossible, making saliva collection an appealing alternative. Saliva is less invasive to obtain than either blood or urine, and does not invoke privacy concerns to the same extent as does urine.
DNA testing is used for purposes of paternity, genealogy, disease susceptibility, and forensics, among others. Blood samples, buccal swabs, and saliva are commonly used for DNA tests. Collecting saliva is less invasive than collecting blood, and saliva collection can provide a larger, and therefore perhaps more reliable sample than buccal swabs.
Saliva samples are commonly collected by one of two methods: intra-oral sponge absorption and direct expectoration. An example of the first is U.S. Pat. No. 4,580,577 to O'Brien, et al., which discloses an absorbent mass that is masticated by the donor until saturated. The mass is placed in a squeezing device to expel saliva into a holding chamber, out of which a test aliquot can be removed. Sponge or sponge-like absorption methods are disclosed in numerous other patents, teaching variations such as added reagents, salivation promoters, preservatives, flavorings, chemical stabilizers, and a plurality of samples, among others.
However, such known saliva collection devices can be inconvenient to use, may be prone to leakage and contamination, and may yield inaccurate results due to user error.